On Sat, Apr 18, 2015 at 12:16:48AM +0200, Mateusz Guzik wrote: > I would say this makes the use of seq counter impossible. Even if we > decided to fall back to a lock on retry, we cannot know what to do if > the slot is reserved - it very well could be that something called > close, and something else reserved the slot, so putting the file inside > could be really bad. In fact we would be putting a file for which we > don't have a reference anymore. > > However, not all hope is lost and I still think we can speed things up. > > A locking primitive which only locks stuff for current cpu and has > another mode where it locks stuff for all cpus would do the trick just > fine. I'm not a linux guy, quick search suggests 'lglock' would do what > I want. > > table reallocation is an extremely rare operation, so this should be > fine. It would take the lock 'globally' for given table. It would also mean percpu_alloc() for each descriptor table... -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
